Hi all, Playing with mod_opus came up with the following. I am trying to recompile the codec with 8Khz and 40ms ptime. I am not familiar with the codec internals and not really sure what parameters should I change... In mod_opus.c : Line 59: int bitrate_bps = codec->implementation->bits_per_second; int use_vbr = 1; int complexity = 10; int use_inbandfec = 1; int use_dtx = 1; int bandwidth = OPUS_BANDWIDTH_FULLBAND; int err; I suppose that the bandwidth must be changed to OPUS_BANDWIDTH_NARROWBAND and use_vbr=0 and I haven't found yet whether the FEC parameter is passed to opus encoder. And in Line 184 , I think the following parameters must be changed switch_codec_interface_t *codec_interface; int samples = 480; int bytes = 960; int mss = 10000; int x = 0; int rate = 48000; int bits = 32000; Can you propose any values about these parameters to achieve 8khz with 40ms packet time? Thanks for any help, Dimosthenis